Yieldable pad for stamp pads



April 13, 1954 w. K. MuNsoN YIELDABLE PAD FOR STAMP PADS INVENTOR WH ITNEV K. MUNSON ATTQRNE Patented Apr. 13, 1954 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to what are generally known as stamp pads used in conjunction with rubber stamps for applying stamped imprints on packages, envelopes and the like. More particularly, the invention deals with a pad structure formed of reinforced sponge rubber body in producing an effective transmission of ink to the rubber stamp and to cushion the operation of applying the ink to the stamp.

The novel features of the invention will be best understood from the following description, when taken together with the accompanying drawing, in which certain embodiments of the invention are disclosed and, in which the separate parts are designated by suitable reference characters in each of the views and, in which:

Fig. 1 is a plan View of a stamp pad made according to my invention with parts of the con struction broken away and with parts in section; and

Fig. 2 is a partial section on the line 2`2 of Fig. 1 and omitting part of the background showing.

In Fig. l of the drawing, I have illustrated at I the base of a stamp pad which is formed of molded rubber, the base having a depending peripheral rim portion I I, part of which is shown in Fig. 2 of the drawing. The bottom wall I2 of the pad is reinforced at intervals by spaced rim members I3. The bottom wall I2 has spaced wells or receptacles I4, one of which is shown in section in Figure 2 of the drawing. These wells are open through the upper surface of the wall I2, and arranged in the wells are inking pads, one of which is shown at I5. At I6, I have indicated in part in Fig. l of the drawing a cover for the pad which is hinged to two blocks I1 at the rear portion of the pad. The cover I5 is adapted to fit over the raised rim or wall portion I3 to form an enclosure for the pad. The wall portion I3 forms a large chamber I9 substantially rectangular in form which chamber is adapted to receive one of my improved yieldable pad units 2U.

The wall IB has at corner portions thereof pivot recesses 2I which open inwardly from the side portions of the raised wall as clearly noted in Fig. 1, and these recesses are adapted to receive angular pivot extensions 22 on a center reinforcing plate 23 of the unit 20. portions 22 serve to retain the unit 20 against accidental displacement from the chamber I9. On the other hand, 22 provides a pivotal mounting which permits the unit to swing upwardly for re-inking the pads I5, and also, it provides a The pivot f reverse mounting of the unit 20 in the chamber or compartent I9. The reinforcing plate 23 can be composed of any suitable and substantial rigid material, and here, plastic, metal or fibrous materials can be used. Secured to upper and lower surfaces of the plate 23 are sponge rubber sheets 24, 24 which can be cemented or otherwise secured into position. The dimensions of the sheets 24, 24 are such as to fit snugly but freely within the walls I8 in the manner clearly illustrated in the drawing.

'I'he reinforcing or petitioning plate 23, which is disposed between the two sheets 24, 24' oi sponge rubber, has distributed over the area thereof a multiplicity of apertures 25 as clearly noted in part in Fig. 1 of the drawing. These apertures permit the feed of ink from the Dads I5 to the surface of the sponge rubber sheet which is disposed uppermost and in such manner as to prevent overinking but, at the same time, to distribute the ink over the surface to provide eflicient operation in movement of a rubber stamp downwardly on the pad in the customary operation. The thin sponge rubber sheets 24, 24'

. will provide the desired cushion effect which will facilitate proper inking. However, the reinforcing strip or sheet will minimize the degree of cushioning at least to the exposed sheet so as to prevent inking beyond the bounds of the lettering or type of the pad, thus preventing smudging imprints as sometimes is experienced in the use of ink pads of the type and kind generally known. The use of the pad unit of the type and kind under consideration will minimize the degree of pressure required in performing a proper inking of a rubber stamp. In other words, the common practice of pounding a rubber stamp on a rubber pad can be dispensed with.

It will be understood that the reinforcing sheet 23 is within boundaries of the sheets 24, 2li except for the protruding pivot and coupling ends 22. At 26, in Fig. 1 of the drawing, I have shown centrally of the forward edge of the base I, a rubber catch device for engaging an adjacent edge of the cover IE when the latter is in closed position. Downward pressure on the catch 2E will release the cover for movement into open position.

It will be understood that the body portion Ii! of the pad is constructed of firm but yieldable rubber whereas the pad unit 20, aside from its reinforcing and backing sheet 23, is composed of yieldable material of any type and kind. How ever, I have found in practice that sponge rubber sheets are suitable for this purpose. In the use of the device, it will be apparent that when pressure is applied to the upper surface of the pad unit 20, for example the surface of the sheet 24, this pressure is distributed through the sheet 23 to the sheet 24'; and While the pressure is loca1- ized to some degree on the upper sheet 24, it becomes more widespread on the lower sheet 24', thus operating to distribute the ink from the pads I 5 overthe entire area of the unit 20. The sheet 23 may be said to comprise a control element Which controls the transmission of ink from the wells or other source of supply to the inking surface of the pad unit and, at the same time, prevents or checks excessive transmission of the ink.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A stamp pad of the character described comprising a base having Wells opening through the upper surface of the base, inking pads in said wells, the pad Yhaving raised wallsY surrounding and spaced from said Wells to form a compartment on said base, a cover hinged to the base controlling access to said compartment, a pad unit detachably supported in the compartment of said base, said unit comprising upper and lower facing sheets of yieldable material and an intermediate perforated reinforcing sheet, means for retaining said unit against displacement from said compartment, and said last named means comprising coupling members integral with and extending outwardly from said reinforcing sheet and engaging the raised walls bordering said compartment.

2. A pad unit for stamp pads of the character described, said unit comprising an apertured sheet of firm reinforcing material, facings on upper and lower surfaces of said apertured sheet, said facings comprising sponge rubber sheets, and said apertured sheet having outwardly projecting mounting members integral with opposed edge portions thereof.

Referenes oued in the fue of this patent UNITED STATES PATENTS Number Name Date 1,323,487 Payne Dec. 2, 1919 1,518,756 Rapley et al. Dec. 9, 1924 1,577,081 Sengbusch Mar. 16, 1926 2,290,488 Munson July 21, 1942 

